What is a "journal"?

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What is a "journal"?

Peng Yu
Hi,

https://www.sqlite.org/lockingv3.html#rollback

"When a process wants to change a database file (and it is not in WAL
mode), it first records the original unchanged database content in a
rollback journal. The rollback journal is an ordinary disk file that
is always located in the same directory or folder as the database file
and has the same name as the database file with the addition of a
-journal suffix. The rollback journal also records the initial size of
the database so that if the database file grows it can be truncated
back to its original size on a rollback."

I got confused about the above statement about the rollback journal.
The sentence "The rollback journal ..." appears to be a definition.
But it is not.

I think that the following can be considered as a definition. Given
the above sentence appears in a section named "4.0 The Rollback
Journal". I think it should be changed to a definition to avoid
confusion.

https://www.sqlite.org/tempfiles.html

"A rollback journal is a temporary file used to implement atomic
commit and rollback capabilities in SQLite."

Regarding the choice of the word "journal", the only relevant entry
about "journal" in the Oxford dictionary is this. Is "journal" just a
fancy way of saying "record file"? Thanks.

"""
2 a daily record of news and events of a personal nature; a diary.
• Nautical a logbook.
• (the Journals) a record of the daily proceedings in the British
Houses of Parliament.
• (in bookkeeping) a daily record of business transactions with a
statement of the accounts to which each is to be debited and credited.
"""

--
Regards,
Peng
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Re: What is a "journal"?

Peter da Silva-2
In programming a journal is a file or other data structure containing a
series of change records but can be replayed to reconstruct an operation.

On Thu, 30 Jan 2020, 05:29 Peng Yu, <[hidden email]> wrote:

> Hi,
>
> https://www.sqlite.org/lockingv3.html#rollback
>
> "When a process wants to change a database file (and it is not in WAL
> mode), it first records the original unchanged database content in a
> rollback journal. The rollback journal is an ordinary disk file that
> is always located in the same directory or folder as the database file
> and has the same name as the database file with the addition of a
> -journal suffix. The rollback journal also records the initial size of
> the database so that if the database file grows it can be truncated
> back to its original size on a rollback."
>
> I got confused about the above statement about the rollback journal.
> The sentence "The rollback journal ..." appears to be a definition.
> But it is not.
>
> I think that the following can be considered as a definition. Given
> the above sentence appears in a section named "4.0 The Rollback
> Journal". I think it should be changed to a definition to avoid
> confusion.
>
> https://www.sqlite.org/tempfiles.html
>
> "A rollback journal is a temporary file used to implement atomic
> commit and rollback capabilities in SQLite."
>
> Regarding the choice of the word "journal", the only relevant entry
> about "journal" in the Oxford dictionary is this. Is "journal" just a
> fancy way of saying "record file"? Thanks.
>
> """
> 2 a daily record of news and events of a personal nature; a diary.
> • Nautical a logbook.
> • (the Journals) a record of the daily proceedings in the British
> Houses of Parliament.
> • (in bookkeeping) a daily record of business transactions with a
> statement of the accounts to which each is to be debited and credited.
> """
>
> --
> Regards,
> Peng
> _______________________________________________
> sqlite-users mailing list
> [hidden email]
> http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users
>
_______________________________________________
sqlite-users mailing list
[hidden email]
http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users